Remove old JSON and YAML docs syntax
Remove old JSON and YAML docs syntax

This change stops generating JSON (cfn) and YAML example snippets
for resource types. These are ancient and only cause clutter in
the docs.

Change-Id: I94d3a3400f0e9ba8404c2da4364e5f9acc7dc4b2

gonzolino/heat,steveb/heat,dragorosson/heat,openstack/heat,takeshineshiro/heat,cryptickp/heat,jasondunsmore/heat,noironetworks/heat,maestro-hybrid-cloud/heat,maestro-hybrid-cloud/heat,pratikmallya/heat,cryptickp/heat,noironetworks/heat,dragorosson/heat,srznew/heat,jasondunsmore/heat,cwolferh/heat-scratch,cwolferh/heat-scratch,rh-s/heat,dims/heat,steveb/heat,dims/heat,gonzolino/heat,rh-s/heat,openstack/heat,pratikmallya/heat,takeshineshiro/heat,srznew/heat,miguelgrinberg/heat,miguelgrinberg/heat